Had a short stroke due to improper gas tube alignment with FSB. The gas tube hole size appears to be
correct but only 3/4 of it is exposed at the gas port. This has caused much frustration. I drilled the hole out 1/8" & the rifle is locking & functioning properly. I have ordered another from another manufacture. Is there a way to tell which is out tolerence, tube or FSB? I suppose I could pull a working one off another rifle.